Mild traumatic brain injury (MTBI) refers to an injury to the head and includes damage to the brain (Levin, Eisenberg, & Benton, 1989; McHugh, 2002). The damage is caused by an external physical force and may produce an alteration in state of consciousness, impairment of cognitive or physical functioning, and disturbances of behavioral or emotional functioning (Schutt, 1999). The definitions of MTBI vary. The terms “closed head injury,” “traumatic brain injury,” “mild brain injury,” “minor brain injury,” and “concussion” are used interchangeably with MTBI (Gasquoine, 1997). MTBI may cause a lifelong impairment. Studies suggest that at least some adults with MTBI experience poor verbal processing, learning, and retention (Bell, Primeau, Sweet, & Lofland, 1999); poor attention and concentration (Bigler & Snyder, 1995); behavior impairments (Hartlage, Durant-Wilson, & Patch, 2001); depression (Busch & Alpern, 1998); occupational disabilities and chronic symptoms (Binder, 1997); and poor quality of life (QOL; Bédard et al., 2003; Berger, Leven, Pirente, Bouillon, & Neugebauer, 1999). MTBI is a stressful life event that may impact a person physically, psychologically, and socially. Furthermore, MTBI may cause a person to react by exhibiting complex adverse behaviors (Martelli, Zaster, & MacMillan, 1998). Challenges to daily activities after MTBI may produce significant effects in QOL.
Social support is a self-report measure that assesses the various types of assistance or help that a patient receives from family, friends, and others. As a holistic system interacting continuously with the environment, persons with MTBI must be considered in the context of their social support. Research shows that a high level of social support helps people attain a high QOL (Brown, McCauley, Levin, Contant, & Boake, 2004), whereas low social support may cause stress and depression (Bay, Hagerty, Williams, Kirsch, & Gillespie, 2002; McCauley, Boake, Levin, Contant, & Song, 2001). In patients with MTBI, group support from participants who share similar experiences helps avoid prolonged loss of productivity and poor perceived QOL (McCauley et al., 2001). In addition, many studies have reported that social support affects family functioning (Brown et al., 2004; Ergh, Hanks, Rapport, & Coleman, 2003; Ergh, Rapport, Coleman, & Hanks, 2002). Social support refers to the perceptions of patients with MTBI toward (a) family members, a spouse, friends, and others who provide or may provide assistance and (b) satisfaction regarding the support that these patients receive.
Ferrans described QOL as “a person’s sense of well-being that stems from satisfaction or dissatisfaction with the areas of life that are important to him/her” (Ferrans, 1990, p. 15). Ferrans and Powers concluded that a person with high QOL is satisfied in the aspects of life that are important to him or her (Ferrans, 1990, 1997; Ferrans & Powers, 1992, 2014). This definition of QOL captures both an individual’s satisfaction with his or her functions and his or her perception of importance of these functions in daily life. Despite the fact that QOL has been investigated for decades, it is not a well-developed concept in nursing care or theory (Ferrans, 1997). In contrast, it has acceptance as a multidisciplinary evaluation (Ferrans, 1997). Exploring the QOL of patients with MTBI may support the conceptual framework and the value of measurement in this particular population. This study measured QOL in four domains: health and functioning, psychological/spiritual, social and economic, and family. Both the satisfaction with and the importance of various aspects of life in those four domains comprise the QOL. The scores for each aspect are positively related to the significance of impact on QOL.
The purposes of this cross-sectional descriptive study were to (a) explore post-MTBI QOL, (b) determine the extent of social support, and (c) identify factors associated with QOL among post-MTBI Thai adults.
The setting for this study was the Maharat Nakhon Ratchasima Hospital (MNH), a 1000-bed tertiary hospital in Nakhon Ratchasima Province, Thailand. Sample selection was purposive. The potential subjects were defined using the hospital’s database. Subjects included patients who experienced an MTBI during the past 3- to 12-month period. Potential subjects who had been discharged from the hospital with International Classification of Diseases, version 10 (ICD-10) Codes S.00 (superficial wound), S.01 (head wound), S.02 (skull fracture), S.06 (intracranial injury), S.07 (compression injury), or S.09 (other head injury) were invited to participate.
Potential subjects with a history of multiple head injuries, congenital or organic learning disorders, premorbid psychiatric disorders or neurological disorders unrelated to MTBI, or other central nervous system diseases were excluded. Furthermore, patients with a documented Glasgow Coma Scale (GCS) score < 13 during the first 72 hours after admission were excluded. Finally, patients who had experienced their MTBI less than 3 months ago or more 12 months ago were excluded.
Social support was measured using the Social Support Questionnaire short form (SSQ6) (Sarason, Johnson, & Siegel, 1978; Sarason, Sarason, Shearin, & Pierce, 1987). The SSQ is a six-item scale that provides a measure of the number of persons available for support (availability) and satisfaction with the available support system (satisfaction). The satisfaction scores used a 6-point scale ranging from “very satisfied” (6) to “very dissatisfied” (1), with higher scores indicating more support and better satisfaction. The range of the SSQ6 availability subscale is 0–54, and the range of the SSQ6 satisfaction subscale is 6–36. The SSQ6 earned scores for internal reliability of .90–.93 for both the availability and satisfaction subscales when tested on 217 undergraduate students (Sarason et al., 1987). The SSQ6 showed significant divergent validity when it was compared with the Multiple Adjective Affect Check List (r = −.26 for the number subscale and r = −.17 for the satisfaction subscale) and the UCLA Loneliness Scale (r = −.49 for the number subscale and r = −.59 for the satisfaction subscale; Sarason et al., 1987). The SSQ6 has been used on populations of patients with MTBI and yielded high specificity by its ability to discriminate the differences in scores between MTBI (mean score = 2.53) and general trauma (mean score = 3.13; Brown et al., 2004).
QOL was measured using the Quality of Life Index (QLI; Ferrans & Powers, 1992). The QLI is designed to measure both the satisfaction with and the importance of various aspects of life. Important scores are used to weight the satisfaction levels, with higher scores reflecting higher levels of satisfaction with the associated aspect of life. Items that are rated with higher important scores have more impact than those items with fewer scores. The QLI consists of two parts: (a) measurements of the satisfaction with various aspects of life and (b) the measurement of the importance of the same aspects. Scores were calculated for overall QOL and for four domains: health and functioning, psychological/ spiritual, social and economic, and family (Ferrans, 1997; Ferrans & Powers, 1992, 2014). The total possible score for the QLI ranged from 0 to 30, with higher scores indicating better QOL. The QLI-Cardiac version in Thai (Petchprapai, 1998), the QLI-Stroke version, and the QLI-Generic version were used to create a modified version that is appropriate for subjects with MTBI.
Internal consistency reliabilities were tested for all questionnaires. The Cronbach’s alpha coefficients were high, with all over .7, including the SSQ-Availability (.915), the SSQ-Satisfaction (.917), the QLI-Satisfaction (.944), and the QLI-Importance (.933). These Cronbach’s alpha coefficients indicate that the questionnaires are of high quality.
Data Collection Procedures
After receiving approval from the human subjects’ review boards at the MNH, the principal investigator (PI) identified potential subjects from the hospital’s database. Next, the PI mailed the consent packet to all of the potential subjects and waited for 2 weeks for the subjects to review and consider participating in this study. The PI made a call to all potential subjects who mailed in the opt-in postcard to arrange an interview.
All of the subjects were interviewed by telephone at a time and a place of the subject’s choosing. The interview consisted of 100 questions and lasted approximately 30 minutes. The interview questions were the same for each subject (same order, same words): a demographic datasheet, the SSQ6, and the QLI. Chart data were collected after the interview. Day of injury, gender, age, marital status, GCS, length of stay (date of admission and date of discharge), blood alcohol level (if available), and duration of time since the MTBI were collected from the medical records of the subjects by a research assistant who was trained by the PI.
The SPSS for Windows Version 15.0 was used for data analysis. Descriptive statistics were computed to describe the extent of factors, social support, and QOL among Thai MTBI. Pearson’s correlations for continuous variables to QOL were calculated to determine the factors associated with QOL. Chi-square correlations were used for categorical variables.
Protection of Human Subjects
The institutional committees of MNH approved this study, and adult post-MTBI patients were the subjects. All subjects were informed about the purpose of this study. Participation in this study was voluntary, and each subject could withdraw at any time. There were no direct benefits to the subjects for participating in this study, and their decisions regarding participation did not affect the services that they received from the hospital.
Approximately 461 invitation letters and consent forms were sent to eligible subjects who were admitted to the hospital because of concussion, mild head injury, mild brain injury, or closed head injury during the past 3–12 months. From the hospital’s database, most patients had been involved in motor vehicle crashes, falls, or physical assaults. There were 363 men (78.7%) and 98 women (21.3%). Their overall age ranged from 18 to 82 years. The largest age group was younger than 29 years (41.4%), and the average age was 36 years. Over a period of 4 months, 135 consent forms were returned, yielding a return rate of 29%. The ratio of men-to-women among the 135 participants was 83.7% to 16.3%. The median age was 36.0 years, and the mean age was 37.73 years. Although only 29% of the eligible subjects were included in this study, their age and gender were not significantly different from the entire population of 461 eligible subjects.
For the 135 subjects, length of stay in the hospital ranged between 3 and 90 days, with a mean of 8 days. Time since injury was between 4 and 12 months, with an average of 8 months. Most of the subjects were men, ranging in age from 18 to 78 years, with an average of about 40 years. All subjects were Buddhist. About half of the subjects were married; 58 were single; and 11 were separated, divorced, or widowed. Level of education ranged from 4 to 18 years of schooling, with an average of 7 years. All of the subjects were employed or had student status before the injury. Furthermore, 95.6% returned to their job or school afterward, with 65.9% of those in this category returning at the same level and 61.5% returning at full-time status. The income of subjects ranged between 2000 and 20,000 Baht/month, with mean (M) = 4309.63 and standard deviation (SD) = 2466.62 (32 Bath = 1 USD). Information pertaining to presence of alcohol at the time of injury was missing in 60% of the medical records. Of those records containing information related to blood alcohol level, 31.9% report of its presence at the time of injury (Table 1).
Among the 135 subjects, 40% had MTBI without other injuries. Another 60% had other associated injuries, including extremity fractures, maxilla or mandible fractures, blunt trauma to the abdomen, or lacerated wounds. Length of stay in the hospital ranged between 3 and 90 days, with a mean of 8 days. Time since injury ranged between 4 and 12 months, with an average of 8 months. Subjects spent between 3 and 180 days recovering at home, with an average of about 50 days. The average duration of posttraumatic amnesia was 5 minutes, and the duration of loss of consciousness was close to 2 minutes. The average GCS was 14 at 30 minutes after injury and 15 at 72 hours after injury. The total postconcussion symptom scores were between 30 and 120, with an average of 50. The average scores for the three subscales were 17, 17, and 16, respectively (Table 2).
Social support was reported for the total score and the two subscale scores: availability and satisfaction. The average score for total social support was 73, with average scores for the availability and satisfaction subscales at 40 and 33, respectively.
The possible range of QLI scores is 0–30, with higher scores indicating a better QOL. In this study, the actual range for the 135 subjects was 18–29.74, with an average total score of 24, an average health and functioning domain score of 22, an average psychological and spiritual domain score of 25, an average social and economic domain score of 25, and an average family domain score of 27.
QOL was then regressed simultaneously on all factors. The model was supported (adjusted R2 = .157, F = 2.923, p < .001). The contribution of all stimuli explained 15.7% of the variance in QOL (p < .0125). Social support was the only variable that was identified as a significant factor in this statistical model (the unstandardized regression coefficient [B] = 1.024, the standardized coefficient [beta] = .374, t = 4.490, p < .0125). There were eight cases that had a Cook’s distance of over .0336 (4 / n − k − 1; when n = 135 and k = 15). Another regression model without outliers was run, and the R2 was improved.
Because the Cook’s distance suggested that eight of the cases were outliers, those cases were excluded, and another regression model was performed. Similar to the previous model, QOL was regressed simultaneously on all of the stimuli (Table 2). The model was supported, and the R2 increased when compared with the previous model (adjusted R2 = .246, F = 4.160, p < .001). The contribution of all of the stimuli explained 24.6% of the variance in QOL (p < .0125), with social support showing the strongest explanatory power (B = 1.105, beta = .414, t = 5.041, p < .001), followed by ability to return to work/school (B = 4.067, β = .223, t = 2.706, p < .01) and length of hospital stay (B = 0.081, β = .224, t = 2.672, p < .01; Table 3). Dubin–Watson was 1.579, tolerances were .785–.961, and Variance Inflation Factor were 1.041–1.274.
The power of the statistics in the model after the exclusion of outliers was calculated using G-Power Version 3 (Faul, Erdfelder, Lang, & Buchner, 2007). An effect size of .479 was retrieved from an R2 of .324 (explained variance by regression = 519.294, unexplained variance = 1085.072). A critical F of 2.946 and a power of .989 were generated using sample size = 127, alpha = .001, and number of df = 13 (Table 3).
The level of social support reported by subjects with MTBI in this study was high, with averaged availability scores of 40 (range = 18–54), satisfaction scores of 33 (range = 24–36), and total scores of 73 (range = 49–90). Only one study in the literature used the same measure of social support (Brown et al., 2004), which reported scores differently. The scores for social support in this study were recalculated to be comparable with this previous study, giving new availability scores of 6.63 (SD = 1.73), which was higher than the availability scores among MTBI in the previous study (2.94, SD = 1.79). Total social support and satisfaction with social support scores were not reported in that study.
It is not surprising to find that social support is high among Thai subjects with MTBI. Thai families are typically extended families. Adult offspring frequently live in the same house as their parents, and relatives live in close proximity to one another. Relatives visit each other frequently especially when one of the family members gets sick or injured. After their injuries, most of the subjects with MTBI stayed at home and were likely taken care of or comforted by their family members. Even after they returned to work, their family members were still concerned about their well-being. These concerns were evident to the PI, as several family members contacted the PI on behalf of the subject when the invitation letters were received at home. Some of the family members raised their concerns about the consequences after MTBI by calling the PI to report additional information.
The Thai social network is strong, with social support not limited to family members. It is common to see that many subjects with MTBI also mention their community leaders, when asked about the availability of social support. Because many subjects were involved in traffic accidents and the legal system, subjects with MTBI relied on their community leaders to help them deal with legal problems. All treatment expenses related to traffic accidents in Thailand are covered by the Bureau of Motor Vehicles Insurance, even if the victims are not insured. Patients with MTBI thus must deal with filling out many forms and the complicated government bureaucracy. Therefore, the community leaders, who are powerful and knowledgeable, are very helpful for the subjects.
The subjects received both physical care and emotional support from their family members, together with help from other social networks. The subjects with MTBI perceived that they received high social support. This findings of high social support is consistent with different studies conducted with different Thai sample populations, including subjects with tuberculosis (Jittimanee, 2005) and postpartum depression (Srisaeng, 2003).
QOL scores were high in this study. The total average score for QOL (23.88) was slightly higher than QOL scores among Thai subjects with valvular heart disease (22.80; Petchprapai, 1998). Considering that subjects with MTBI were not as symptomatic as subjects with valvular heart disease, this difference is not surprising. Supporting the findings related to social support, the family domain earned the highest scores, whereas the health and functioning domain earned the lowest scores.
Only one prior study explored QOL among MTBI, although with results that were significantly different. The QOL score among adults with MTBI in the prior study was lower than that of the normal control population (Emanuelson, Andersson Holmkvist, Björklund, & Stålhammar, 2003). No control sample was used in this study to determine the difference between the QOL scores of subjects and the general adult population. The QLI has been tested in college students, but normative data were not reported (Ferrans & Powers, 1985).
The health and functioning scores were reported as 22 in this study. These scores indicate that subjects with MTBI did not experience many symptoms after their injury and that they were satisfied with their health. Another reason is that there were only three items in the health and functioning domain that were related to post-MTBI symptoms. The rest of the health and functioning questions were concerned about health and functioning in general.
The psychological and spiritual scores were reported as 24. This finding is consistent with the minimal presence of depressive symptoms noted by the subjects. The social and economic scores were reported as 25. This domain contained of items that were related to either social support or social integration. Because the subjects in this study had high social support scores and most were able to resume their social activities and return to work, it was not surprising to see that their scores in this domain were high. High scores in this domain and the family domain may be the reasons that underlie the relationship between QOL and social support.
The family domain scores (28) were the highest scores among all of the domain scores. Furthermore, social support scores correlated positively with QOL scores. It is noted that the social support measure used in this study assessed the same dimension of social or family support as in the QOL (satisfaction). Because both measures examined similar concepts related to social support, it is not surprising that both scores were in the high ranges and were correlated.
In terms of QOL, only social support correlated positively with QOL (r [effect size] = .394). Our finding of a positive relationship between social support and QOL is similar to findings among subjects with mixed severity of brain injury (Farmer, Clark, & Sherman, 2003). This positive relationship has been commonly found across other subject groups such as patients with chronic heart failure (Bennett et al., 2001), dementia caregivers (Haley, Levine, Brown, & Bartolucci, 1987), patients with stroke (Kim, Warren, Madill, & Hadley, 1999; King, 1996), and elderly Intensive Care Unit patients (Kleinpell & Ferrans, 2002).
The reasons for the positive relationship between social support and QOL are that the measures of social support and QOL tap the same dimension—satisfaction. Twelve items in the QLI and in the SSQ6 measure the same attributes.
Limitations of the Study
This was a cross-sectional study that used a telephone survey technique to ask 100 questions over a telephone call time of approximately 30 minutes. Administering a psychological measurement using a telephone survey technique may be inappropriate because it is very difficult to retain a respondent’s concentration for 30 minutes and because this duration of time increases the risk of recall bias. However, all subjects with MTBI were not hospitalized and were not currently making follow-up visits to their doctors. In addition, the subjects were informed that they could continue the interview on another day if necessary.
The subjects in this study were recruited from only one tertiary hospital. Therefore, the findings might not be generalizable to all clients with MTBI.
For future study, it is recommended that concurrent data collection with a matching normal population be included to provide baseline information. Future studies that compare outcomes between different groups distinguished by gender, age category, diagnosis (with and without multiple injuries), time since injury, and social support status should be conducted. Health education related to the potential long-term effects of MTBI injury should be administered routinely before patient discharge.
The findings in this study provide information about the importance of social support to support a good QOL after MTBI. Healthcare assessment on admission for patients with MTBI should include social support or social network support to facilitate recovery. Patients should be educated to help them evaluate their postinjury outcomes.
Measures used in this study were translated into Thai, tested, and yielded high reliability coefficients. These tools may be implemented among Thai adults with MTBI to assess their outcomes.
This study of QOL after MTBI among Thai adults indicated that social support was the most powerful predictor for QOL. The findings of this study provide a basis for future studies, which may be longitudinal, comparative, or predictive, with a reduced number of relevant variables. Several measures used in this study were reliable and may be used within the Thai context. Health education or printed information about outcomes after MTBI is recommended.
The author would like to thank Chris Winkleman, PhD, RN, ACNP, FCCM, FAANP, Associate Professor at the Frances Payne Bolton School of Nursing at Case Western Reserve University, for her time and effort in providing help extensively throughout the research process. Great thanks also go to Ferrans E. Carol for permission of using the QLI in this research.
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